Subtract 21/50 from 20/81
20/81 - 21/50 is -701/4050.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 50 is 4050
Next, find the equivalent fraction of both fractional numbers with denominator 4050 - For the 1st fraction, since 81 × 50 = 4050,
20/81 = 20 × 50/81 × 50 = 1000/4050 - Likewise, for the 2nd fraction, since 50 × 81 = 4050,
21/50 = 21 × 81/50 × 81 = 1701/4050 - Subtract the two like fractions:
1000/4050 - 1701/4050 = 1000 - 1701/4050 = -701/4050
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